Need Some Help!

dewercs

Ok, this is a model specific question so please don't move this thread. I'm a 250/450 B rider that is a pretty good mechanic and my suspenion is set up with proper sag and a reasonable set up, the suspenion is stock but well maintained. I ride a 07 yz250f and 07 yz450f, I'm having more of a problem with the 450. Last season I had no problem at all and the bike handled like is was on rails. This year when I turn into a turn and start to lean the bike the front tire is breaking loose, I ride on intermediate to hard pack dirt, I hav used bridgestone intr. and hard pack, and maxxis intermediate and hard pack tire with a wide variety of tire psi settings... in other words I have been testing! What I don't get is nothing has changed from last season except I have been changing tires and psi settings to try to find some grip. I'm open to any suggestions. I reviewed video footage of my rideing and my form and body position looks good and is the same it was last year. I had a couple thoughts of fork oil hieght may be to high or taking out a little sag to put more wieght on the front wheel, but it is the same as last year. Sorry for the long post, and advice is greatly appreciated!!